Comment 17 for bug 2036761

Hello Norbert, thank you for your testing and results.

This issue is caused by the fact that Ubuntu server and Ubuntu desktop use different types of awk. Ubuntu server uses gawk (GNU awk) by default while Ubuntu desktop ships with mawk which has less features than gawk and does not have support for the -i argument hence the error "awk: not an option: -i".
If your workflow depends on ppa-purge I recommend installing gawk (apt install gawk) and this will fix the issue temporarily while I get a permanent fix for ppa-purge.

side note: I am not sure why there is a difference in the default awk installed/used between Ubuntu desktop and server maybe it is an oversight and should be labeled as a bug? or maybe there is another reason that someone could clarify? To my knowledge gawk is the default version of awk on most linux distros and has all the features of mawk.

I will add gawk as a dependency to ppa-purge but I still believe that someone should look into why different versions of awk are shipped between server and desktop since this means shell scripts are not compatible between server and desktop by default.